Is that "need" or "find convenient"? 1 in a million gives you an error of roughly 132 feet (40 metres) in the circumference of the Earth. 1 in 100 million br

Is that "need" or "find convenient"? 1 in a million gives you an error of roughly 132 feet (40 metres) in the circumference of the Earth. 1 in 100 million brings that down to 1.32 feet (0.4 metres). 1 in 100 million is a mere 8 decimal places (out of the billions of decimal places that we've computed for pi.)